Abstract: An underwater trenching apparatus for burying pipeline and the like including a frame for positioning about the pipeline to be buried, a drive roller system operatively connected to the frame for driving the frame along the pipeline and including at least one pair of opposed rollers, each of the rollers having a curved pipe contact surface having a radius less than the radius of the pipeline to be buried and configured to grasp about 40 percent of the circumference of the pipe, the arms to which the rollers are mounted pivot about a shaft which is removably mounted to the frame, and a cutting system attached to the frame for cutting a trench, the cutting system includes at least one pair of rotating discs rotating about a horizontal axis, and having water nozzles extending out from them, the water forced out of the nozzles scoops the seabed and disperses it up, away from the bottom of the trench. The pair of discs are mounted so that they can be moved up and down as well as rotated in and out.

Abstract: This invention relates to the self-propelled underwater trenching apparatus and method for burying pipelines, cables and the like with minimum underwater diver supervision. The apparatus includes a frame having frame members positioned about the pipeline and buoyancy tanks with variable positions. Drive rollers are connected to the frame members for drive engagement with the pipeline. The frame members are movable by power rams about vertical and horizontal pivots selectively to engage or disengage the drive rollers with the pipeline. Oscillating water jet nozzles are secured to the apparatus for preselected sweeping movement to cut away the bottom formation to enable the pipeline to be buried in the trench so formed.

Abstract: This invention relates to the self-propelled underwater trenching apparatus and method for burying pipelines, cables and the like with minimum underwater diver supervision. The apparatus includes a frame having frame members positioned about the pipeline. Drive rollers are connected to the frame members for drive engagement with the pipeline. The frame members are movable about a pivot to selectively engage into or disengage rollers out of drive engagement with the pipeline. The apparatus also may include extensible means to move the pivot axis laterally or transversely of the pipeline. The formation is cut away by water jets secured to the apparatus to enable the pipeline to be buried in the trench formed. Upon meeting an obstruction on the surface of the pipeline, power rams in the fore portion of the frame member separate the frame member that may bend the frame member to bring the forward drive rollers out of driving engagement with the pipeline.

Abstract: An underwater self-propelled buoyant trenching apparatus for burying a pipeline or cable on the bottom of a body of water. Water jets on a frame cut the trench, and a venturi operated eductor means sucks up and discharges the cuttings. The apparatus is motivated by a drive roller that is resiliently urged against the pipeline. Forward guide rollers sense the pipeline direction and act to torque the apparatus onto the centerline of the pipeline. The arrangement of the jet nozzle minimize the rearward thrust. Buoyant outrigger tanks adjust the attitude of the apparatus over the pipeline. The hose bundle is buoyant due to the oversize air hose.

Abstract: A gear head wrench particularly suited for use in applying torque to bolts without transferring torsional stresses to bolt-receiving structures. The wrench is characterized by a coupling including a socket, for connecting a bolt head with a torque multiplying gear-train, provided within a housing having an annulus concentrically related to the socket and adapted to be coupled with a spacer interposed between the bolt head and the juxtaposed surface of the bolt-receiving structure for applying a balancing counter-torque to the spacer as torque is applied to the bolt head whereby the bolt-receiving structure is substantially isolated from torsional stress. As a result of the foregoing, the operator of the wrench is substantially isolated from any forces which may be imposed.